Python NGF College

# Chapter 1,2: Basics

example 1.

# a=5

# b=3

# c=a+b

# print(c)

example 2.

# x = “COE”

# print(x)

# x=99

# print(x)

example 3.

# x, y, z = “COE”, “PMKVY”, “NGF”

# print(x,y,z)

# print(x+y+z)

# print(x) 

# print(y)

# print(z)

# x=5

# print(x)

# x = y = z = “Brown”

# print(x)

example 4.

t=”my”

u=’name is’

v=”___”    #your name

print(t+u+v)

subject= “hindi”

mobileNo = “xyz”

Variables

myvariablename0=0

myVariableName1=1

MyVariableName2=2

my_variable_name3=”hello”

example 5.

a=15

b=9

c= a-b

example 6.

costOfToy=15

discount=9

total=costOfToy-discount

print(total)

print(type(total))

# Chapter 3: Data Types

age = 25

is_student = True

average_grade = 89.5

name = “Alice”

print(age, is_student, average_grade, name)

# Chapter 4: Numbers

x = 10

y = 3

sum_result = x + y

diff_result = x – y

prod_result = x * y

div_result = x / y

print(sum_result, diff_result, prod_result, div_result)

# Chapter 5: Strings

course_name = “Python Programming”

instructor = “John Doe”

full_message = “Welcome to the ” + course_name + ” course, taught by ” + instructor + “.”

print(full_message)

# Chapter 6: Lists, Tuples, and Dictionary

fruits = [“apple”, “banana”, “cherry”]

point = (3, 7)

person = {

    “name”: “John”,

    “age”: 30,

    “is_student”: False

}

print(fruits)

print(point)

print(person)

# Chapter 7: Lists, Tuples, and Dictionary (Continued)

fruits.append(“orange”)

point = point + (5, 2)

person[“occupation”] = “Engineer”

print(fruits)

print(point)

print(person)

# Chapter 8: Exercise – Temperature Conversion

celsius_temperature = 25

fahrenheit_temperature = (celsius_temperature * 9/5) + 32

print(“Celsius:”, celsius_temperature)

print(“Fahrenheit:”, fahrenheit_temperature)

# Operators in python

# Chapter 9: Arithmetic Operators

a = 9

b = 2

addition = a + b

subtraction = a – b

multiplication = a * b

division = a / b

modulus = a % b

exponentiation = a ** b

print(addition, subtraction, multiplication, division, modulus, exponentiation)

# Chapter 10: Relational/Comparison Operators

x = 5

y = 8

greater_than = x > y

less_than = x < y

equal_to = x == y

not_equal_to = x != y

print(greater_than, less_than, equal_to, not_equal_to)

# Chapter 11: Logical Operators

good = True

best = False

logical_and = good and best

logical_or = good or best

logical_not_good = not good

logical_not_best = not best

print(logical_and, logical_or, logical_not_good, logical_not_best)

# Chapter 12: Assignment Operators

x = 10

x += 5

# x -= 3

# x *= 2

# x /= 4

print(x)

# # Chapter 13: Bitwise Operators

# num1 = 10

# num2 = 7

# bitwise_and = num1 & num2

# bitwise_or = num1 | num2

# bitwise_xor = num1 ^ num2

# bitwise_left_shift = num1 << 2

# bitwise_right_shift = num1 >> 1

# print(bitwise_and, bitwise_or, bitwise_xor, bitwise_left_shift, bitwise_right_shift)

# Chapter 14: Identity Operators

x = [1, 2, 3]

y = [1, 2, 3]

z = x

is_x_y = x is y

is_x_z = x is z

is_x_not_y = x is not y

# print(is_x_y, is_x_z, is_x_not_y)

# Chapter 15: Membership Operators

fruits = [“apple”, “banana”, “cherry”]

is_apple_present = “apple” in fruits

is_mango_absent = “mango” not in fruits

print(is_apple_present, is_mango_absent)

# Chapter 16: Operator Precedence

result = 5 + 3 * 2 – 6 / 3

# The result is calculated as 5 + (3 * 2) – (6 / 3)

print(result)

# Conditional Statement

# 1. If Statement

age = 18

if age >= 18:

    print(“You are an adult.”)

# 2. If-Else Statement

age = 15

if age >= 18:

    print(“You are an adult.”)

else:

    print(“You are a minor.”)

# 3. Elif Statement (Multiple Conditions):

score = 85

if score >= 90:

    grade = “A”

elif score >= 80:

    grade = “B”

elif score >= 70:

    grade = “C”

else:

    grade = “D”

print(“Your grade is:”, grade)

# 4. Nested If-Else Statement

is_raining = True

has_umbrella = False

if is_raining:

    print(“It’s raining.”)

    if has_umbrella:

        print(“You can go outside with an umbrella.”)

    else:

        print(“Stay indoors.”)

else:

    print(“It’s not raining, enjoy the weather!”)

# String Methods:

# Single Quotes: Create a string using single quotes.

my_string = ‘Hello, World!’

# Double Quotes: Create a string using double quotes.

my_string = “Hello, World!”

# Triple Quotes: Create a multi-line string using triple quotes.

multi_line_string = ”’

This is a

multi-line

string.

”’

#—————– Accessing Characters

# Indexing: Access characters by index (0-based).

my_string = “Hello, World!”

char = my_string[0]

print(char)  # Gets the first character ‘H’

# Slicing: Get a substring using slicing.

my_string = “Hello, World!”

sub_string = my_string[7:12]

print(sub_string)  # Gets ‘World’

# Negative Indexing: Access characters from the end.

my_string = “Hello, World!”

last_char = my_string[-1]

print(last_char)  # Gets the last character ‘!’

#————- String Methods

# len(): Get the length of a string.

my_string = “Hello, World!”

length = len(my_string)  # Returns 13

# str.upper() and str.lower(): Convert a string to uppercase or lowercase.

my_string = “Hello, World!”

upper_case = my_string.upper()  # Converts to uppercase

lower_case = my_string.lower()  # Converts to lowercase

# str.strip(): Remove leading and trailing whitespace.

my_string = “Hello, World!”

stripped = my_string.strip()  # Removes leading/trailing spaces

# str.replace(): Replace occurrences of a substring.

my_string = “Hello, World!”

new_string = my_string.replace(‘Hello’, ‘Hi’)  # Replaces ‘Hello’ with ‘Hi’

# str.split(): Split a string into a list of substrings.

my_string = “Hello, World!”

words = my_string.split(‘,’)  # Splits on commas

# str.join(): Join a list of strings into one string.

my_string = “Hello, World!”

joined_string = ‘-‘.join([‘Hello’, ‘World’])  # Joins with a hyphen

# or

my_string = [“Hello”, “World”]

joined_string = “-“.join(my_string)  # Joins with a hyphen

# str.find() and str.index(): Find the index of a substring.

my_string = “Hello, World!”

index = my_string.find(‘World’)  # Returns index of ‘World’ (7)

# ——————- String Formatting

# f-Strings: Use f-strings for string interpolation.

name = ‘Alice’

greeting = f‘Hello, {name}!’  # Creates ‘Hello, Alice!’

# str.format(): Format strings with placeholders.

name = ‘Akash’

formatted = ‘Hello, {}!’.format(name)  # Same result as f-string

eg.2

name = ‘Akash’

age=26

multiple_placeholders=”My name is {}, I’m {}”.format(name, age) #Output: My name is Akash, I’m 26

# String Concatenation: Combine strings with the + operator.

name = ‘Ajay’

combined = ‘Hello, ‘ + ‘World!’  # Creates ‘Hello, World!’

combinedWithVar = ‘Hello, ‘ + name # Creates ‘Hello, ‘Ajay

# String Interpolation using % (Older Python Versions):

In older Python versions, you can use the % operator for string interpolation:

name = “Ajay”
age = 30
message = “My name is %r and I am %d years old.” % (name, age)

print(message)

#Output: My name is ‘Ajay’ and I am 30 years old.

In string formatting, the placeholders like %s, %d, %r, and %f are known as format specifiers, and they are used to define how values should be formatted and inserted into a string.

%s: This is used for string formatting. It is used to insert a string into the formatted string.

%d: This is used for integer formatting. It is used to insert an integer into the formatted string. The %d specifier is typically used for whole numbers.

%r: This is used for representing any Python object as a string. It is known as the “repr” specifier. It inserts the string representation of an object into the formatted string. It’s often used for debugging and displaying a more detailed representation of an object.

%f: This is used for floating-point (decimal) formatting. It is used to insert a floating-point number into the formatted string. It allows you to control the precision and formatting of floating-point numbers, including the number of decimal places.

# ————Escape Sequences

# Escape Sequences: Use escape characters for special characters.

# Newline (\n): Used to insert a newline character into the string.

Newline=”hello how are you \n sanjay”
print(Newline) # Output: This is a newline: \n is treated as a newline character.

escaped_string = ‘This is a newline: \\n’

print(escaped_string)  # Output: This is a line: \n

# In this example, the double backslash \\ is used to escape the backslash itself.

# Tab (\t): Used to insert a tab character into the string.

tabbed_string = ‘This is a tab: \\t’

print(tabbed_string)  # Output: This is a tab: \t

# Single Quote (\’): Used to include a single quote character within a single-quoted string.

single_quote_string = ‘He said, \’Hello!\”

print(single_quote_string)  # Output: He said, ‘Hello!’

# In this example, the single quote within the single-quoted string is escaped using \’.

# Double Quote (\”): Used to include a double quote character within a double-quoted string.

double_quote_string = “She said, \”Hi!\””

print(double_quote_string)  # Output: She said, “Hi!”

# Similarly, you can use \” to include a double quote within a double-quoted string.

# Backslash (\\): Used to include a literal backslash character within the string.

backslash_string = ‘This is a backslash: \\\\’

print(backslash_string)  # Output: This is a backslash: \\

# To include a backslash itself in the string, you need to escape it with another backslash, resulting in \\\\.

#————— String Checks

# str.startswith() and str.endswith(): Check if a string starts or ends with a substring.

my_string = “Hello, World!”

starts_with = my_string.startswith(‘Hello’)  # True

ends_with = my_string.endswith(‘!’)  # True

# str.isalnum(), str.isalpha(), str.isdigit(): Check if the string contains alphanumeric characters, alphabetic characters, or digits, respectively.

my_string = “Hello, World!”

is_alnum = my_string.isalnum()  # False (contains spaces and punctuation)

is_alpha = my_string.isalpha()  # False (contains spaces and punctuation)

is_digit = my_string.isdigit()  # False (contains letters and punctuation)

# str.islower() and str.isupper(): Check if the string is in lowercase or uppercase.

my_string = “Hello, World!”

is_lower = my_string.islower()  # False (contains uppercase)

is_upper = my_string.isupper()  # False (contains lowercase)